I live on 4th floor of a seven-storey building. It's been a month since I noticed these strange things growing on my ceiling. It looks like mud when observed closely.
At first I cleared it with brush which can be seen in the picture as light stains. But it grew again. The darker one is how it looks like now.
The other side of the wall from which this thing grows is the bathroom. Above the bathroom there is a small compartment for storing things. The door of the compartment can be seen in the picture.
I've never seen anything like this. What is this thing? And how can I get rid of it? As mentioned above clearing with a brush doesn't help.